what other option in python keymap line for 'PRESS'?
Enum as below:

value (enum in ['ANY', 'NOTHING', 'PRESS', 'RELEASE', 'CLICK', 'DOUBLE_CLICK', 'CLICK_DRAG', 'NORTH', 'NORTH_EAST', 'EAST', 'SOUTH_EAST', 'SOUTH', 'SOUTH_WEST', 'WEST', 'NORTH_WEST'])


You can find the reference here: KeyMapItens

If you want to simulate holdup method, use the 'PRESS' and 'RELEASE' with if stament. Or maybe 'CLICK_DRAG'